Astronomical School’s Report, 2017, Volume 13, Issue 2, Pages 91–94

https://doi.org/10.18372/2411-6602.13.14
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UDC 524.31

About time of hydrogen burning in stellar entrails. New formulas for approximation

Zakhozhay V.A., Zabuga S.I.

V.N. Karazin Kharkiv National University, Svobody Sq. 4, 61022 Kharkiv, Ukraine

Abstract

The relationship between the duration of nuclear reactions and initial mass of the star is an important component a wide variety of astrophysical problems. In particular, the links between combustion times of hydrogen burning determines and initial mass of the star the residence time on the main sequence stars. Results of calculations star modern models were utilized with the sun (population I) and zero (population III) content of heavy chemical elements, which contained data on nuclear hydrogen burning time. Search dependencies held by least squares using a standard package of Microsoft Excel “Search Solutions” program, with a further analysis of the results. We used three kinds of functional relationships: The logarithmic power functions, logarithmic and exponential functions inverse log-linear functions. Establishing communication wires so that the scrip squares deviation was minimal in the approximate function. Given the fact that the maximum star mass with the sun and zero metal content is limited to 150 solar masses and 500–600, respectively, not all the obtained functional dependencies required to satisfy the requirement of the relationship: Star with large masses are on the main sequence less time. It was found that some of the dependencies have received at least investigated mass range that does not meet the physical sense. The minimum value of the sum of squared deviations responds logarithmically exponential function with three or four free members. All the obtained approximation formulas that describe the dependence of the nuclear combustion conduit by weight of star age zero time interval for weight and elemental composition of stars, are new and have not previously been proposed for use in such classes of problems.

Keywords: main sequence; statistical laws; stellar population

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